The present invention relates to truck mounted mobile drilling rigs, and more particularly to an improved truck mounted mobile drilling rig which can be used with any of several drilling methods.
The common mobile drilling rigs now in use mount a mast at the rear end of a large truck which may be retracted to lie horizontally or nearly horizontally over the truck, but which can be swung to an upright, vertical position for drilling. In the ordinary drilling operation, the truck will back up to align the drilling mast at the rear over a proposed or existing hole. The truck is then stabilized and leveled by suitable outriggers at each end of the truck.
Ordinarily the drill rig truck will carry the machinery necessary to provide suitable power to compress air and to pump liquid as needed, depending upon the drilling equipment associated with the mast. If necessary, auxiliary vehicles can be used to carry extra compressors and the like. The drilling equipment carried on the truck can be of various types for different drilling methods. For example, impact type drills will include pile drivers, air hammers and churning bits. Rotary type drills will include roller and fishtail bits attached to single and double wall drill stems, diamond bits and augers. One can find different, specialized types of drilling rigs for these special drilling methods. Pile drivers are ordinarily used in overburden and unconsolidated sediments. Rotary drills are usually used for drilling wells. Diamond drills on different types of vehicles are used for obtaining hard rock core samples. Wagon drills carry jackhammers to drill in hard rock for setting explosives. Auger drills specialize in drilling holes and/or obtaining core samples in soil and overburden.
The general trend and development has been to adapt each drill rig for a special use and the operator will specialize in a single type of drilling such as water well drilling. However, field operations are not always suitable for a single drilling method and sometimes different drilling methods must be combined and several different types of drilling rigs are needed for the same job. A rotary, or impact type of drill is needed to drive a shaft through overburden and to rock before an exploratory diamond drill can be used to cut to take cores from the bedrock formation. This use of different drill rigs is an expensive proposition. Also, a difficult problem and a tedious chore can arise in setting a drill rig over an existing hole where precise alignment is important.
It follows that there is a real and definite need for an improved drilling system to better cope with problems such as those outlined above and the present invention was conceived and developed with such and other considerations in view. The invention comprises, in essence, a multi-purpose mobile drill rig having a mast carried at the rear end of a truck which is shiftable from a horizontal retracted position over the truck to a vertical operative position for drilling. Also, this mast can drill at selected inclined positions if necessary. The mast carries a multi-purpose drill support which can carry any of several different types of drills including a pile driver, a rotary drill, a diamond drill and a jackhammer also called an air hammer. The drill rig may use air or water or a combination of both and it is capable of quickly shifting from one type of drilling method to another.
It follows that objects of the present invention are to provide a novel and improved multi-purpose drill rig which: is adapted for drilling by any one of several drilling methods; can quickly and easily shift from one drilling method to another without changing the set-up of the rig and without moving off the hole; can quickly and easily shift a drill out of alignment with the hole when other work is necessary such as setting casing or retrieving a drill stem; and which is an economical, rugged and durable unit.
With the foregoing and other objects in view, all of which more fully hereinafter appear, our invention comprises certain constructions, combinations and arrangements of parts and elements as hereinafter described, defined in the appended claims and illustrated in preferred embodiments in the accompanying drawings, in which: